This invention relates to packaging of electronic and optical components.
Modern electronic components have design goals that are conflicting. Generally electronic components emit electromagnetic (EM) radiation and such EM radiation often interferes with the performance of other components. Often in-order to assemble electronic components into a system some of the components are shielded from stray EM radiation. Typically such shielding is provided by a conductive enclosure.
Another design goal relates to the heat produced by electronic components. Often such heat must be removed from the component to avoid excessively high temperatures that can damage or interfere with the component or its operation. Cooling can use a fan to move cooling air past the component to carry off the excess heat. Often heatsink structures are used with or without fans to aid in the conduction of the heat from the electronic components.
In many instances the enclosure that provides adequate EM shielding leads to difficulties in removing heat efficiently from the component. A solution to this conflict is to die cast an enclosure,for an electronic component, which provides both the EM compatibility (EMC) and the thermal coupling to the electronic component.
In general, in one aspect the invention features a method for producing an enclosed electronic component. The method includes: extruding a first heatsink member having a plurality of cooling structures disposed on a first surface; extruding a second heatsink member having a plurality of cooling structures disposed on a first surface; disposing an electronic component board on a second surface of one of the first and second heatsink members; and joining the first and second heatsink members, with a pair of joining members to form a sealed enclosure for the electronic component board with the sealed enclosure providing electromagnetic isolation of the electronic component and a thermal pathway to remove heat from the electronic component.
Embodiments of the method may include any one of the following features.
The extruding the first and second heatsink may further include: forming first ribs on the second surfaces of the first and second heatsinks, with the electronic component board having conductive bands on top and bottom surfaces thereof that are aligned with portions of the first ribs.
The joining may further include: joining the top and bottom conductive bands of the electronic component board to the first rib of the first and second heatsink members respectively.
The extruding the first and second heatsink may further include: forming second ribs on the second surfaces of,the first and second heatsinks with the electronic component board having a second pair of conductive bands on top and bottom surfaces thereof that are aligned with portions of the second ribs and joining further includes: joining the first and second top conductive bands of the electronic component board to the first and second rib of the first heatsink member and joining the first and second bottom conductive bands of the electronic component board to the first and second rib of the second heatsink member respectively.
The above method may further include forming positioning pins that align the first heatsink member, the second heatsink member, and the electronic component board.
A first portion of the positioning pins may provide vertical positioning and a second portion may provide horizontal positioning of the electronic component board.
The joining may include: securing contacting regions of the first and second heatsinks, the electronic component board, and a pair of joining members with screws, and sealing regions about the contacting regions with conductive gasket material.
The extruding of the top or bottom heatsink may include forming a substantially cylindrical channel in the top or bottom heatsink wherein the diameter of the channel is suitable for forming threads that engage the screws.
The joining may include welding contacting regions of the first heatsink, the second heatsink, the electronic component board and a pair of joining members.
The joining may include securing contacting regions between the first heatsink, the second heatsink, the electronic component board and a pair of joining members by using a combination of screws and sealing regions about the contacting regions with conductive gasket material for some of the contacting regions and welding for other contacting regions.
The electronic component board may further include heat transfer structures that provide thermal coupling between the electronic component and the top or bottom heatsink.
In another aspect, the invention features a method for producing an enclosure for an electronic component. The method includes: extruding a first heatsink member having a plurality of cooling structures disposed on a first surface; extruding a second heatsink member having a plurality of cooling structures disposed on a second surface; joining the first and second heatsink members with a pair of joining members to form a sealed enclosure, the sealed enclosure providing electromagnetic isolation of the electronic component and a thermal pathway to remove heat from the electronic component.
The joining may include: securing contacting regions of the first and second heatsinks, and the pair of joining members with screws and sealing regions about the contacting regions with conductive gasket material.
The extruding of the top or bottom heatsink may include forming a substantially cylindrical channel in the top or bottom heatsink wherein the diameter of the channel is suitable for forming threads that engage the screws.
The joining may include: welding contacting regions of the first and second heatsinks, and the pair of joining members.
The joining may include: securing contacting regions of the first and second heatsink members, and the pair of joining members by using a combination of screws and sealing regions about the contacting regions with conductive gasket material for some contacting regions and welding the contacting regions for other contacting regions.
In another aspect, the invention features a packaged electronic component. The package includes: an extruded first heatsink member having a plurality of cooling structures disposed on a first surface wherein the cooling structures have smooth surfaces characteristic of an extruded part; an extruded second heatsink member having a plurality of cooling structures disposed on a first surface wherein the cooling structures have smooth surfaces characteristic of an extruded part; an electronic component board disposed within an enclosure provided by the first and second heatsink members, and a pair of joining members secured; and wherein the first and second heatsink, the joining members, and the electronic component board are joined at contacting regions to form a sealed enclosure for the electronic component board with the sealed enclosure providing electromagnetic isolation of the electronic component and a thermal pathway to remove heat from the electronic component.
The first and second heatsink may include: a first rib on the second surface of the first and second heatsinks and the electronic component board includes conductive bands on a top and a bottom surface of the electronic board and wherein the top and bottom conductive bands of the electronic component board and the first ribs of the first and second heatsink members sealed with conductive gasket material.
The first and second heatsink may further include: a second rib on the second surface of the first and second heatsinks and the electronic component board includes second conductive bands on the top and the bottom surface of the electronic component board and the second ribs of the first and second heatsink members sealed with conductive gasket material.
The package may further include positioning pins that align the first heatsink member, the second heatsink member, and the electronic component board.
The positioning pins provide either vertical or horizontal positioning of the electronic component board.
The contacting regions may include screws that secure the contacting regions of the first heatsink, the second heatsink, the electronic component board and the pair of joining members and regions of conductive gasket material about the contacting regions.
The top or bottom heatsink may have a substantially cylindrical extruded channel in the top or bottom heatsink wherein the diameter of the channel is suitable for forming threads that engage the screws.
The electronic component board may further include a heat transfer structures that provide thermal coupling between the electronic component and the top or bottom heatsink.
The contacting regions may include welds of the first heatsink, the second heatsink, the electronic component board and a pair of joining members.
The contacting regions of the first heatsink, the second heatsink, the electronic component board and a pair of joining members may include a combination of screws and conductive gaskets for some of the contacting regions and welds for other contacting regions.
One or more aspects of the invention may provide one or more of the following advantages.
The invention provides an enclosure for an electronic component with fine cooling structures. Unlike alloys used for die casting that typically have lower heat conductivities than pure metals the enclosure offers improved conductivity. In addition the fine, high surface area features that provide efficient thermal coupling between the electronic components and the cooling gases are easier to produce. Furthermore, while die-casting is typically relatively expensive and requires a relatively lengthy time from product conception to product manufacture, extrusion is less expensive and has a relatively short time from concept to product.